This invention relates in general to respirators and in particular to a new and useful respirator which includes a housing having a chemical cartridge for liberating oxygen and binding carbon dioxide and a breathing gas passage with a breathing connection at one end and a portion of the passage which provides an area cooler.
The invention relates to a respirator with regeneration of the respiratory air through a chemical cartridge binding CO.sub.2, which cartridge is arranged in the respiration path between a breathing connection and a breathing bag.
Such a respirator has become known from German OS 25 04 881. In the known respirator the chemical cartridge is arranged between a breathing connection and a breathing bag, so that at horizontal flow through the chemical cartridge the exhaled air flows into the breathing bag. During inhalation, the air is returned from the breathing bag into the breathing connection via the check valve while by-passing the chemical cartridge. Such a respirator is used in so-called circulation operation. As the exhaled air flows through the chemical cartridge, an exothermic reaction takes place through which CO.sub.2 is bound and O.sub.2 given off. The warmed exhalation air thus regenerated is cooled during its stay in the breathing bag to a temperature such that the wearer can inhale it again. Disadvantageous in respirators in circulation operation is the fact that they require for the return of the inhaled air special channels or chambers separated from the air conduction of the exhalation air. To avoid this, it is known to operate respirators in the pendulum system. Here the inhalation air as well as the exhalation air pass through the chemical cartridge. Then, however, heat exchangers must be provided between the chemical cartridge and the breathing connection for the cooling of the inhalation air. Such heat exchangers are known for example from German PS 335 931 and from German GM 19 81 991. However, if these known heat exchangers would, as is readily possible, be connected to a respirator which with omission of the inhalation air return ducts necessary for respiration in circulation operation had been modified into a respirator for pendulum operation, the known advantage of the compact and space-saving respirators easy to handle for the user would be lost through the expensive, heavy and space-requiring heat exchangers.